Journal article
Use of stochastic models to estimate the growth of the Port Jackson shark, Heterodontus portusjacksoni, off eastern Victoria, Australia
J Tovar-Ávila, VS Troynikov, TI Walker, RW Day
Fisheries Research | ELSEVIER SCIENCE BV | Published : 2009
Abstract
Three stochastic models were used to describe the growth of Heterodontus portusjacksoni off eastern Victoria, Australia. The models are based on a reparametrization of the von Bertalanffy growth model to take account of length-at-age heterogeneity, and incorporate random variation of the von Bertalanffy growth coefficient (k), using three different probability distribution functions (pdfs): Weibull, gamma and log-normal. They were fitted to the lengths of 179 specimens (79 females and 100 males), and associated age estimates obtained by counting growth bands in the inner trunk dentine layer of the dorsal-fin spines. The species is relatively long-lived (maximum estimated age of 35 years for ..
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Awarded by Instituto Nacional de Pediatria
Funding Acknowledgements
We thank the anonymous referees who improved this paper with their comments and corrections. Observers and commercial fishers from Victoria are acknowledged for providing the specimens, Matt Reardon is acknowledged for collecting some data and spines, and staff of the Central Ageing Facility at the Primary Industries Research Victoria (PIRVIC) Queenscliff for providing advice on the processing of samples. This research was supported by an Australian Fisheries Research and Development Corporation grant (FRDC Project 2003/023 to Terence 1. Walker). The principal author was supported by a Postgraduate Scholarship from the National Science and Technology Council (CONACyT) and the National Fisheries Institute (INP) from Mexico and by a David Hay Writing Up Award from the University of Melbourne for preparation of this paper.